1. Field of the Invention
This invention relates to ethanol solvent-based hairspray compositions which employ a specific type of silicone copolyol which causes the hairspray composition to contract upon drying and thereby improve the body and hair setting properties of the hairspray composition.
2. Description of the Prior Art
Various types of silicone materials, and more specifically silicone copolyols such as those designated by The Cosmetic, Toiletry and Fragrance Association ("CTFA") name of "dimethicone copolyols", have been suggested for use in hairspray compositions to modify the properties of the compositions to leave the hair with various properties such as ease of brushing, to give the hair a softer feel, to reduce tackification after spraying or to impart luster to the hair.
For example, DOW CORNING.RTM. 190 and 193 Surfactants are water soluble silicone glycol copolymers which are said to be useful in hairspray products to impart luster, detackification and hold properties in hairspray compositions when used at 0.1 to 1% of the composition. DOW CORNING.RTM. Q2-5220 Resin Modifier is said to be a dimethicone copolyol as a resin modifier for hairsprays, mousses, setting lotions and styling gels which is readily compatible with ethanol and water. At a use level of 0.1 to 1.0%, the DOW CORNING Q2-5220 Resin Modifier is said to plasticize resins, making them softer, more flexible and less tacky.
European Pat. Appln. No 116,207 to Elliott et al. teaches an aerosol hairspray formulation comprising a hair-holding resin dissolved in a solvent system such as ethanol, and aerosol propellant and from 0.5 to 10% by weight of the formulation of at least one cyclic silicone such as dimethylsiloxane cyclic tetramer or dimethylsiloxane cyclic pentamer in addition to the dimethicone copolyol such as DOW CORNING 193 surfactant.
The examples in the Elliott et al. Patent indicate that the dimethylsiloxane cyclic tetramer or pentamer is used in amounts equal to or in excess of 10 parts of the tetramer or pentamer to 1 part of dimethicone copolyol. Linear and cyclic polydimethylsiloxanes are known to be hydrophobic and are therefore not compatible with water. Dimethicone copolyol such as DOW CORNING Q2-5220 resin modifier tend to form uniform films when compositions containing the silicone and a hairspray resin dissolved in an ethanol solvent system are sprayed out on a substrate such as a glass slide or the hair. Introduction of a hydrophobic silicone such as a dimethylsiloxane cyclic pentamer causes the film to contract toward the center of the substrate as the composition dries. The combination of the dimethicone copolyol and dimethylsiloxane cyclic pentamer which results in a film that contracts upon drying is thus said to impart an "autophobic" effect on the hairspray composition.
A number of hair spray compositions are commercially available and have been marketed for a number of years which contain dimethicone copolyol and also which contain dimethicone copolyol and cyclomethicone as stated on the package label of the product. For example, FINESSE pump and FINESSE Aerosol hairspray formulations sold by Helene Curtis Industries, Inc. list both dimethicone copolypol and cyclomethicone on their label. The product, when sprayed on a glass slide, was noted to have an autophobic effect in that the composition tended to contract towards the center of the glass slide upon drying. The FINESSE hairsprays were based on an ethanol solvent system.
The Elliott et al. patent application discusses the disadvantages of only using a dimethicone copolyol such as DOW CORNING 193 surfactant in hairspray compositions and suggest the use of dimethylsiloxane cyclic tetramer or pentamer in such such compositions, presumably to obtain this autophobic effect. A rather significant level of dimethylsiloxane cyclic tetramer or pentamer must be used to overcome the natural tendency of dimethicone copolyols that are water soluble to form an evenly spread film upon drying. The autophobic effect of this combination of silicone materials can be used to improve the body of hair sprayed with the hairspray resin since the hairspray resin tends to contract as it dries and thus adheres the fibers of the hair together at the points where one strand crosses another.
The use of dimethicone copolyols in cosmetic and personal care formulations is discussed in a paper by F. C. Vick in Soap/Cosmetics/Chemical Specialties for May, 1984, Vol. 60. p. 36ff entitled "Structure/property Relationships for Silicone Polyalkyleneoxide Copolymer and Their Effects or Performance in Cosmetics." The composition of the copolymers discussed very widely in molecular weight and the content and type of alkyleneoxy block present, i.e., ethyleneoxy or propyleneoxy units, present in the copolymers discussed. However, the dimethicone copolyols described in this paper have a 0.1% cloud point of at least 41.degree. C. or more which indicates that these silicone dimethicone copolyols are rather water soluble.
Union Carbide Corporation also markets a series of dimethicone copolyols under the trademark SILWET. The Union Carbide Data Sheet No. F-44773 12/80-5M entitled "SILWET.RTM. Surface Active Copolymers", 1980. page 13 suggests the use of SILWET copolymers L-720, L-7600 and L-7002 for use in personal care products, specifically for hair care products. Nothing is mentioned concerning the use of SILWET.RTM. L-7602 in hair care applications. A 1987 Union Carbide Data Sheet entitled "SILWET.RTM. SURFACTANTS FOR USE IN PERSONAL CARE PRODUCTS" lists SILWET L-7602 among 5 others for personal care use, some of which included improving hair sheen and soft feel. The recommended starting use level is 1.0% by weight of the total formulation.
U.S. Pat. No. 3,928,558 to Cheesman et al. teaches that certain polydimethylsiloxane-polyoxyalkylene block copolymers can be incorporated into hairspray compositions comprising a film forming resin in a cosmetic vehicle. These polymers have a ,silicon content of 15 to 25%, a molecular weight of from,1,200 to 5,000 and a viscosity at 25.degree. C. of 3 to 10 poises and their inclusion makes the resin easier to brush out from the hair. Cheesman et al. teach that all three variables are critical in obtaining the proper polydimethylsiloxane-polyoxyalkylene block copolymers which can be used in their invention. Cheeseman et al. teaches nothing concerning the presence or absence of an autophobic character to the block copolymers employed in their invention.
U.S. Pat. No. 4,423,041 to Clum et al. teaches detackifying compositions for use in emulsion-type personal care compositions which comprise a mixture of a silicone fluid which can be a dimethylsiloxane cyclic tetramer or pentamer (CTFA name "Cyclomethicone") and a silicone wax in a ratio of from about 9:1 to 1:3. The silicone wax can be a dimethicone copolyol having a molecular weight of about 1,600 to about 2.000. but is required to be a solid or semi-solid at body temperature and must be insoluble in water and insoluble or only slightly soluble in cosmetic oils. Nothing is taught concerning the use of this combination of materials in a hairspray composition.